Method of and apparatus for heating liquefied gas fuel



April 8, 1947. Q. ANDERSON 2,418,44fi

' METHOD OF AND APPARATUS FOR HEATING LIQUEFIED GAS FUEL Filed Oct. 20,1938 2 Sheets-Sheet l p i o. R. ANDERSON 2,413,445

METHOD OF AND APPARATUS FOR HEATING LIQUEFIED, GAS 11mm Filed Oct. 20,1938 2 Sheets-Sheet 2 Patented Apr. 8, 1947 QUEFI D GAS Olaf R.Anderson, Chicago, Ill.,, assignor, by nsane,

assignments, to The Bastian-13 11 8 Chicago, 111., a corporation ofIllinois Application October-20, 1938, Serial No. 236,061

Company; r I

2o Claims, (01. 62-1) This invention pertains both to fuel supplysystems and to refrigeration systems and, more particularly, toutilization of waste heat from the refrigeration system, for the purposeof either vaporizing liquid fuel to form a combustible vapor or gas orfor the purpose of heating or super. heating the pre-formed fuel vaporthereby to improve the combustion and other characteristics thereof, therefrigerant being simultaneously and correspondingly cooled forcondensation or other purposes.

Fuel systems employing liquifled gas such as propane, butane andmixtures thereof, generally utilize an underground storage tank orreservoir I from which the fuel, either in a liquid or in a vaporizedstate, is piped to a furnace or range or other place of use. Since theinventionis primarily of importance in connection with systems in whichthe fuel is in a gaseous or vapor form when burned further reference tosystems in which the fuel is liquid at the burner, will be omitted.

The liquid fuel may be supplied to the storage tank or reservoir by tanktruck and is held under pressure therein subject to use. Earth heat issometimes the sole means to effect vaporization of the liquid fuel butwhere the earth heat may be insumcient, auxiliary means such as a steam7 40 0. and and butane at abo t or 3 or hot water coil in the bottomportion of the storage tank or a pilot heater beneath the tank.

may be used to supplythe heat needed to efieot vaporization and thepressure for delivery. Sometimes the home water supply line is runthrough or in other heat transfer relation to the liquid fuel in thereservoir thereby to deliver its heat to eifectvaporization of the fuel.None of these methods is wholly satisfactory and most of them 2 areunsafe or dangerous or involve expensive equipment including controls,

Since the gas demandsof the consumer vary considerably, neither steamnor hot water coils nor a pilot heater may be used without complicatedand-expensive safety controls and if steam F.) tha it does not hum ef iientlyand but n may s parat out; of a mixture oi propan d utane and t iss paration may any he n he l ne. by conden ation th reot. F r mo e thehutane mev not be vapo i d n. -f portion to t prooanetrom he m ture inthe reservoir r may not volatilize at an. ac o d nsly f. the air-88.5 mxture ra io at he humor is set for a. definite fuel mixture. anyvariatio in the fuel pro ort ons may produce undesi a e flame harac eistics and may requi e c nst read u tmeuts oi the air sas mixture.

rd ngly o e oi the primary objects of the i venti n is to pro ide a simpe but emoient n effectiv me hodof and. a system fo supplvins t e rquisite heat t etteot h mogen us or proportional vapor zatio of liquidfuels such as those above mentioned, to efleot heatin or super ating oth tuel vapors whereby to incre se combustion emoienor and to reduce ore iminate co d nsation o the hea ier iue constituents, o reduce the andexplos on hazards. a d, in short to obviate or reduce the varioudiiliculties here. totore encountered in the vaporization and comon ofliq d fuels oi the typ s menti ed. T invention-is also co cerned with.the r eflicient cooling and condensing o1 refrigerants,

h o d y household retr serator enters many problems to the engineer tramthe standpoint oi di sipat on of the heat absor ed by th re lssorbertype r i erating svsteins i each oaseor hot water is used the expense ofa pump to return condensate or-to circulate the hot water becomes apractical necessity. Where the house water supply is used to supply theliquid fuel with heat, other problems are introduced. If too much heatis absorbed-,from any given volume there is considerable waste h atwhich is diflioult to diss pate. Most h usehold refri era or densersoperate at" temperatures considerably above normal room temperaturesand, accords ns'ly, are in fli i nt. Furthermor t diss tion of heat fromthe retrigerantis not only an economic loss but, when dissipated into aroom, ay make the temperature oi the o m un omtortably high,

herefore. a other object o he invention e side in a method of and in a sstem by h c the inte nal and. absorbed heat of the rei s ant mayberemoved ra idly and em iently t erefromvand may be utilized to carry outthe first object above specified, all to the end that better d o emcientreniserat on m y b e d and that a more eflloient and satisfactory liqd-- to-vapor or gaseous fuel system may be provided.

part oi the problem for Many other objects as well as the advantages anduses of the invention will be appreciated and understood afterreadingthe following description andclaims and after viewing the severalembodiments illu strated in the accompanyingdrawings in which:

other heat conducting medium. If desired the tank 28 may be insulatedbut it is considered preferable not to insulate this tank since ifexcess heat units from the refrigerant are supplied such.

excess may be dissipated through the tank walls (to the atmosphere,whereas, if additional-heat Fig. 1 is a diagrammatic view of a liquid-tovapor fuel system combined with a compressor type refrigeration system,in illustration of one preferred arrangement in which a heat exchangoris placed in parallel with the condenser of the refrigerant system.

Fig; 2 is a view similar to the view of F18. 1

the refrigerant condenser, the view being simplified by omission ofother parts already shown in Fig.1.

, Fig. 3 is a view of, a. part 'of a liquid-to-vapor fuel system similarto the system of Fig. 1 but showing a diflerent means whereby totransfer the waste heat of refrigeration to thefuel, the primaryfunction of the heat, in this case, being to effect homogeneousvaporization of the liquid fuel, and] I I v Fig; 4 is a schematic viewof one type of absorption refrigeration system illustrating one way bywhich a llquid-to-vapor fuel system may be combined therewith incarrying out the objects of the invention. a

The apparatus diagrammatically illustrated in a compressor typerefrigeration system interrelated inheat exchange and operation. Such asystem may be considered as adapted for rural gas supply andrefrigeration purposes or for small but illustrating a heat exchanger inseries with units are needed to heat or to super-heat the fuel: vapor inthe coil I3, the tank may pick up some or all of such additional heatunits by conduction from the atmosphere.

' The heat absorbed from the earth by the liquid fuel in the tank 2 willvaporize a, part-of the liquid fuel thereby to create sufficientpressure within the tank to lift the fuel either in its liquid statethrough the liquid line 5 or in its .gaseous state through the gas line4 to th coil I3 and the place or places of fuel consumption. The

valves 6 and I may be operated to supply either fuel vapor or liquidfuel or a mixture to the supply line 9, as will be understood. If vaporis passing .throughthe supply line 9, the valve I21should be a. pressurecontrol valve whereas, if liquid is passing into line 9,-the valve I2should be an expansion valve. After the .vapor has passed through thecoil I3 and has been heated by the heat units supplied from therefrigerating apparatus including the latent heat'of the refrig-- erantto effect condensation thereof; it passes to the pressure regulator I4and thence to the concommercial plants but is adaptable to other types 2of use. An underground liquid fuel storage tank 2 is provided with afill pipe 3, which in turn may be provided with a safety pressure vent,a vapor outlet pipe 4 and a liquid outlet pipe 5, the normal top levelof the liquid fuel in the tank being indicated by the horizontal dottedline. The pipe lines 4 and 5 may be provided with shut of! valves '8 and1, respectively, and may join through a 'r connection I with a commonsupply line 8 in which'ashut oifvalve I I and either a pressureregulating or expansion valve I2 may be disposed. The low pressuresideof the pressure regulating or expansion valve I2 is connectedwith a coilI3 which in turn is connected with a pressure regulating valve I l atthehigh pressure side of the latter and valve I4 connects at its lowpressure side with whatmaybe termed consumer line I] leading to a burnerI8 or other place of use of the fuel vapor. A pressure released safetyvent on the low pressure side of the pressure regulating valve II isrepresented by the pipe I'I.

An electric motor M drives a refrigerant com pressor C which dischargescompressed refrigerant into the line 2i from which it may flow throughcondenser coil 22 or through a coil 23 to effect condensation thereofand thence through an expansion valvev '24 into an evaporator coil 25 ofa refrigerating box or unit and thence back tothe compressor through areturn line 28. If

desired the fuel or some of it may be used to generate steam in a boilerB the steam -being utilized. in an engine 21 to drive a generator G tosupply electricity to run the motor M, but other means-forsupplying thepower to operate the may be either submerged in the liquid fuel in the.tank-2a or disposed in thermal contact relation Fig. 1 includes aliquid-to-vapor fuel system and If desired the coil 22a may be placed inheat exchange relation with the vapor coil -I 3 in which case the coil23a may be used to dissipate any excess heat not taken out by the vaporin coil II.

InFig. 3 the liquid fuel in tank 2a is heated and vaporized by the wasteheat from refrigerant supplied through. a line 3| and is returned totherefrigerant evaporator through the line 32.

The refrigerant passes through acoil 33 which.

with the tank walls, as may be preferred. Any

I excess heat supplied .to the liquid fuel which W0lfld cause a rise inthe temperature of the liquid fuel above the temperature ofthesurrounding earth would be dissipated into the earth'through the tankwalls. The application of heat to a low. point of the liquid in the tankor to a'low point of the tank will cause convection currents to flow inor boiling of the liquid fuel within the supply tank or reservoir andthereby will tend to homogenize the vapors of the different liquid fuelscomprising the fuel mixture within the tank.

Clonsequentlythe fuel vapors passing into the fuel supply line will beuniform or. substantially uniform in character, that is, will maintainsub- ].stantially definite proportions of constituents until the tankcontents are exhausted.

compressor may be utilized as will be understood.

The fuel vapor coil I3 and the refrigerant condenser coil 23 are placedin heat exchange relatlon with one another, preferably within atank 28which may be filled with water or brine, or

fuel supply tank 2b is connected through a vapor line lb'and aliquidline lb, shut off valves lb and 1b", respectively, with a supplyline- Ob. A

. Fig. 4-, an absorption type refrigeration system is shown incombination with a liquidto vapor fuel supply system. An undergroundsystem.

liquid fuel of. the class including propane and butane and mixturesthereof is stored in an underground reservoir and in heat transferrelation'with the earth and is vaporized for combustion, the'method ofheating the said fuel to vaporize the same which comprises, passing atleast'a part of the waste heat laden vapor'of a refrigerant in a closedrefrigerating system in heat exchange relation with a low portion of thbody of the fuel within the reservoir.

5. In combination, a liquid fuel reservoir, a gas burner, means forconveying vapors from liquid fuel supplied by the reservoir to saidburner, a refrigeration system including a compressor and a closed cyclefor the refrigerant,

and means for transferring heat to be dissipated from the refrigerant toveye'd to said burner.

6. In combination, a liquid-to-vapor fuel supply system including aliquid fuel reservoir, a

the fuel to be convapor burner and a fuel supply line fromsaid reservoirto said burner; a refrigerating system including a compressor and anevaporator, and means for transferring heatv absorbed by refrigerant inthe evaporator to the fuel to be conveyed to the burner through saidfuel supply line. '7. In combination, a' liquid-to-vapor fuel sup- I plysystem including a liquid fuel reservoir, a

vapor burner; and a fuel supply line from said a reservoir to saidburner, a refrigerating system burner and a supply line connecting saidburner and reservoir, a refrigerating system including a compressor, anevaporator, and a condenser, and

.means associating said condenser and said fuel supply line in heattransfer relation. 9. In combination, a liquid-to-vaporfuel supplysystem including an' underground liquid fuel reservoir, a. burner and asupply line connecting said burner and reservoir, 9. refrigeratingsystem including a compressor, an evaporator, and a condenser, and meansincluding apart of said refrigerating system between said compressor andsaid evaporator and associatedwith said fuel system for transferringheat units from the refrigerating system into-said fuel system.

10. In combination, a liquid-to-vapor fuel supply system including aliquidv fuel reservoir, a

burner and 'a}supply line connecting said burner and reservoir, arefrigerating system including a compressor, an evaporator, and acondenser, and means in series with said condenser and associated withsaid fuel system for transferring heat units from the refrigeratingsystem into said fuel system. I v

11. In combination, a liquid-to-vapor fuel supply system including aliquid fuel reservoir, -a burner and a supply line connecting saidburner and reservoir, a refrigerating system'including a compressor, anevaporator, and a condenser, and

' means in parallel with said condenser and associated with said fuelsystem for transferring heat units from the refrigerating system intosaid fuel 12. In combination, an underground liquid fuel reservoir.- 2.gas burner, means for conveying vapors from liquid fuel in saidreservoir to said burner, a refrigeration system ,includinganevaporator, a compressor, and means interconnecting the evaporator andthe compressor in a closed cycle for the refrigerant, the meansconnecting the highpressure side of said compressor with the evaporatorincluding means disposed in heat exchange relation with the liquid fuelin said reservoir.

13. In a system in which liquid fuel of the class including propane andbutane and mixtures 10 in heat'exchange relationship with the earth, acoil in heat exchange relationship with the contents of the tank, meansfor withdrawing said fuel from the tank, and means for maintaining 'auniformity in the fuel mixtures throughout the tankincluding said coiland-means utilizing refrigerant' waste heat for establishing atemperature diff erential between the coil and the contents of the tankto'circulate the contents of the tank convectively.

14. In combination, a vaporizing chamber, means for holding underpressure a liquid-having a boiling point below the freezing point ofwater, means for supplying said liquid to said vaporizing chamber at areduced pressure, a refrigerating system comprising a closed conduit forthe refrigerant including a condenser section in heat exchangerelationship with said vaporizing chambet and an evaporator section inheat exchange relationship with space to be refrigerated, and arefrigerant in said conduit means forconveying heat from saidrefrigerating system to said chamber. 5- '15. In combination, avaporizer including an element defining acircuitous passageway, meansfor holding a fluid having a boiling pointbelow the freezing. point ofwater, means for creating fluid pressure in-said holding means andmainmeans for supplying said fluid in its liquid phase to said vaporizerat a reduced pressure including an expansion valve, a refrigeratingsystem comprising conduit means for the refrigerant including evaporatorand condenser sections in heat exchange relationship with space to .berefrigerated and said vaporizer respectively.

means defining a circuitous passageway, means -.50 for storing a fluidhaving a boiling point below the freezing point of water, means forholding said'fluid in both its vapor and liquid phases and establishinga fluid pressure within the storing means, means for supplying saidfluid in its liquid phase to said circuitous passageway including afluid flow control means, a refrigerating device including conduit meanshaving a refrigerant therein in both its liquid and vapor phases, meansfor transferring heat from a portion of said con- 0' duit means havingvapor therein to said circuitous passageway including a stabilizingelement tending to assume the temperature of said vaporizer and toreceive heat units from said portion of said conduit means withoutcontacting 6 the fluid or refrigerant. i 1'7. In combination, means forstoring fuel un- .der pressure in its liquid and vapor phases, means Ifor dispensing said fluid in its vapor phase including a conduit meansand a pressure reducing e1ement therein, a refrigerating systemincluding a closed cycle for the refrigerant, means for establishing ahigher pressure in one part ofthe' closed cycle including a pressurereducing device, and means for transferring heat from the refrig- 76erant uponthe'high pressure side of said pres thereof is vaporized forcombustion, thecombination of means for storing said fuel in a tank'taining said fluid in its liquid and vapor phases,

16.- The combination of a vaporizer including sure reducing device tothe conduit means upon' said pressure reducing prising a tank having aportion of said fuel conduit downstream of said means in heat exchangerelationship with the tank contents for vaporizing the ,fuel in saidconduit portion, means for means for dissipating heat units from thespent refrigerant, means for transferring heat units from saiddissipating means-to the fuel supplied to said burner, and means drivenby the heat of said burner to move the refrigerant in said refrigeratingsystem.

- 19. In a liquid-to-gas fuel system employing liquid fuel of thecharacter of propane and buextending from a point adjacent the bottom ofsaid supply tank for delivering fueltherefrom, means in said, conduitfor reducing the pressure on liquid fuel therein, a vaporizer comprisinga tank having a portion of said fuel conduit downstream of said means inheat exchange relationship with the tank contents for vaporizingthe fuelin said conduit portion, means for conducting a heat exchange mediumfrom saidheat I source, said means including one branch arranged forsupplying heat'to said tank contents and to the fuel at reduced pressurein said conduit.por-

tion and including also a second branch arranged for bypassing said tankcontents'and the fuel in said conduit portion and for dissipating heatfrom said medium, and means for delivering the vaporized fuel to a pointof use from said conduit portion.-

20. m a liquid-to-gas fuel mam employing liquid fuel of the character ofpropane and -bu-= tane, the combination comprising a source ofhotrefrigerant; a sup ly tank of liquid fuel, 'a fuel conduit extendingfrom a point adjacent the bottom of said supply tank for delivering fueltherefrom, means in said fuel conduit for reducing the'pressureonliquidfueltherein,avaporisercom-' Co Waukesha, Wis.

conducting refrigerant from said source including one branch traversingthe vaporizer tank for supplying heat to said tank contents and to theconduit portion and for dissipating heat from said refrigerant, meansfor delivering the vaporized fuel to a point of use from said conduitportion,

and means for returning cooled refrigerant from 15 tone. the combinationcomprising a source of 1 heat, a supply tank of liquid fuel, a. fuelconduit source.

' OLAF R. ANDERSON.

nnmnmsces crrnp said branches to said Thefollowing references are ofrecord me of this patent:

' UNITED STATES PA'IENTE Number Name Date, Re. 19,350 Munters et al.Oct. 23, 1934 2,099,041 Ullstrand Nov. 16, 193'.

2,059,942 Gibson Nov. 3, 1936 1,935,281 Reed Nov. 14, 1933 1,874,803-Reed Aug. 30, 1932 1,967,271 Smith July 24, 1934 2,105,383 White Jan.11, 193,? 2,127,004 Nelson Aug. 16, 191?. 2,125,842 Eggleston Aug. 2,1938 1,609,758 MacMahon Dec. 7, 1928 1,752,185 Ford Mar. 25, 1930811,168 Dickerson Sept. 20, 1898 FOREIGN PATENTS Number Country 7 Date22,258 Australian Sept. 8, 1929 O'I'HERREFERENCEB nuuean ace-c.Published by Waukesha um inthe' Certificate of Correction Patent No.2,418,446. April 8, 1947. OLAF R. ANDERSON It is hereby certified thaterrors appear in the printed specification of the above numbered patentrequiring correction as follows: Column 6, line 59, claim 2, strike outtherewith and insert instead with the refrigerant; column 7, lines 31and 32, claim 7, strike out a compressor and and insert the same in line31, same claim, after including, first occurrence; and that the saidLetters Patent should be read with these corrections therein that thesame may conform to the record of the case in the Patent Office.

Signed and sealed this 29th day of July, A. D. 1947.

LESLIE FRAZER,

First Assistant C'ommissz'oner 0 7 Patents.

